From 0b92068fe69a8def446bc23f4fde0fc97eb28f1b Mon Sep 17 00:00:00 2001
From: Darth Affe <darthaffe@wyrez.org>
Date: Sat, 8 Apr 2017 15:17:36 +0200
Subject: [PATCH] Fixed DPI-scaling problem in the Ambilight-Example

---
 .../ScreenCapturing/DX9ScreenCapture.cs       | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/Examples/Ambilight/Example_Ambilight_full/TakeAsIs/ScreenCapturing/DX9ScreenCapture.cs b/Examples/Ambilight/Example_Ambilight_full/TakeAsIs/ScreenCapturing/DX9ScreenCapture.cs
index b4cadce..5c212f1 100644
--- a/Examples/Ambilight/Example_Ambilight_full/TakeAsIs/ScreenCapturing/DX9ScreenCapture.cs
+++ b/Examples/Ambilight/Example_Ambilight_full/TakeAsIs/ScreenCapturing/DX9ScreenCapture.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Runtime.InteropServices;
 using System.Windows.Media;
+using Microsoft.Win32;
 using SharpDX;
 using SharpDX.Direct3D9;
 
@@ -27,6 +28,14 @@ namespace Example_Ambilight_full.TakeAsIs.ScreenCapturing
             Width = (int)System.Windows.SystemParameters.PrimaryScreenWidth;
             Height = (int)System.Windows.SystemParameters.PrimaryScreenHeight;
 
+            //DarthAffe 08.04.2017: Fix for system using windows-scaling. The primary screen size is reported 'wrong'.
+            double scaling = GetScaling();
+            if (Math.Abs(scaling - 1.0) > 0.01)
+            {
+                Width = (int)(Width / scaling);
+                Height = (int)(Height / scaling);
+            }
+
             PresentParameters presentParams = new PresentParameters(Width, Height)
             {
                 Windowed = true,
@@ -42,6 +51,19 @@ namespace Example_Ambilight_full.TakeAsIs.ScreenCapturing
 
         #region Methods
 
+        private double GetScaling()
+        {
+            try
+            {
+                int currentDpi = (int)Registry.GetValue("HKEY_CURRENT_USER\\Control Panel\\Desktop", "LogPixels", 96);
+                return 96.0 / currentDpi;
+            }
+            catch
+            {
+                return 1.0;
+            }
+        }
+
         public byte[] CaptureScreen()
         {
             _device.GetFrontBufferData(0, _surface);